In his 2005 book 戦いのベクトル (Tatakai no Bekutoru, The Vector/direction of Attack [roughly]) Yamashita Keigo looked at his use of tengen in chapter 1. At the end of the chapter he wrote that he did not expect to use first play on tengen again. He explained using the diagram below, which was from one of his games analyzed in the book. Black 3 and 5 were typical of his games, attempting to make best use of the attacking potential in the Tengen stone.

Click Here To Show Diagram Code

[go]$$B Yamashita example of a Tengen fuseki
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 4 . . . . . , . . . . 3 , . . . |
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$$ | . . . , . . . . . 1 . . . . . , . . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 5 . . |
$$ | . . . 2 . . . . . , . . . . . , . . . |
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Consider the alternative of 1-4 below. This is a more normal approach to the fuseki with both sides taking control of the corners in turn. Now "a" does not feel like the natural continuation for Black. And if Black plays elsewhere, there is no expectation that White will seize the opportunity to play "a" immediately either. If White went ahead and played there, Black would not be troubled by such a move.

Click Here To Show Diagram Code

[go]$$Bc "a" not a vital point?
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$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 2 . . . . . , . . . . 1 , . . . |
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$$ | . . . . . . . . . . . . . . . . 3 . . |
$$ | . . . 4 . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Yamashita considers playing on tengen an excellent way to study the fundamentals of attacking and the direction of play. It is also a way to move your opponent out of the normal comfort zones. He himself began to play it because when he was moving up and first encountered the really top competitors among the pros, they all seemed to play the fuseki better than he did. He ended up at a disadvantage entering the middle game too often, so he needed to try something different. Although he did quite well with his experiments with tengen, 5-5, and so on, in the end (i.e. once he got better at more 'normal' fuseki) he thought they were a little bit weaker than the usual strategies.

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Dave Sigaty
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21

I'm now at least trying the center shimari. It's a million degrees outside my comfort zone, even with shapenaji's game plan ready to hand.

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Occupy Babel!

The power of a right away split (with black's 3rd move after conquering his two corners; with white its 2nd move leaving one corner open) is (in theory) that it denies your opponent to create big frameworks. Chinese, Kobayashi, Sanrensei, Mini-chinese...all these are impossible if you split early. So the calculation of a split fuseki goes like this:

Advantage: Destroying your opponents ability to build bigger frameworks
Disadvantage: Less points with playing a wedge instead of playing in a corner or play a shimari instead
Neutral 1: your opponent can attack the wedge by basically playing a free shimari move, but usually if you extend your wedge you'll hold sente or the other stone will get under serious attack
Neutral 2: Game will get smallish and complex with a lot of chances to win (even from behind) but also to lose.

I think the split fuseki should be a good way to play go-programs since it gets so complicated that maybe even MC gets on his borders. Split fuseki (esp. as black) were played in the early 30's, but then never again since. With white we see a lot of pro's who approach with the 2nd move immediately, leaving one corner open which is very related to what a split intends. I was a 1k for about 6 years, but when I changed my fuseki style to split fusekis I jumped up to a strong 1d. Therefore I am curious about this fuseki, maybe it has something, maybe it's just a surprise for players and they underachive because of this.